1. Technical Field
This invention relates to a method and apparatus for producing an aqueous paint from a plurality of premixed compositions wherein the apparatus is cleaned during the paint production.
2. Background Art
The traditional manufacture of paint has utilized processes which continuously fill containers with a neutral or base color at the central facility. The containers are transported to the point of sale and stored until resale. The transport and storage in the individual containers adds significantly to the cost of the sold product for it is necessary to inventory a wide variety of paints having different finish characteristics to satisfy consumer demand. For example, the finishes offered for sale range from the traditional flat paint through varying resin compositions up to a high gloss finish. Inventory is maintained for all the different finishes at the point of sale by the merchant.
The manufacture of paint at the central facility can be either a batch process or an extended continuous mixing process. The process typically calls for mixing a pigment containing ground titanium dioxide along with a thickener, a viscosity controlling agent and resin added to the water base. The pigment is a composition with a high percentage solids suspended in water. Storage for any significant period of time of a premixed pigment composition typically results in settling and a non-uniform distribution of constituents throughout the premix. Consequently, manufacturing processes are designed to limit the residence time in premixing containers in order to promote the manufacture of more uniform products.
Accordingly, there is a need for a method and apparatus for the production of an aqueous paint composition from a plurality of premixed compositions that reduces or eliminates the need to store multiple cans of paint. Further, there is a need for the efficient operation and cleaning of the apparatus at the point of sale.